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    <title>Document</title>
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    <script>
        //Array.from
        var weishuzu = { //伪数组
            '0': '1', //'index':value
            '1': '2',
            'length': 2
        }
        var ary = Array.from(weishuzu, item => item * 2);
        //将伪数组转化为真数组 同时通过一个参数函数 进行值操作为*2
        console.log(ary);
        // obj.find
        var person = [{
            name: 'zhangsna',
            age: 18
        }, {
            name: 'lisi',
            age: 12
        }];
        var tar = person.find(item => item.age == 12);
        console.log(tar);
        // obj.findIndex
        let arrr = ['12', '344', '53'];
        let back = arrr.findIndex(item => item > 50);
        console.log(back);
        let arrrr = ['aa', 'bb', 'cc'];
        let backk = arrrr.includes("aa");
        console.log(backk);
        let backkk = arrrr.includes("dd");
        console.log(backkk);
    </script>
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